MPA556S-II and Murmur II Suppressors

The MPA556S-II is a user serviceable can, utilizing a monocore design that gives the end user the ability to service and clean the suppressor without having to send it back to the manufacturer. This MPA556S-II can handle 5.56x45mm, .223, 5.7x28mm, 22LR, 22 WMR and 17HMR with exceptional performance. The DB ratings in 5.56 is in the 133 DB range (10 shot weighted average using NI Labview Software / GRAS ¼” MICs) and in 22LR, the can meters in the 113 DB range. The ability to service the suppressor by the end user allows the can to handle 22LR without shortening the life of the product due to the dirty nature of this ammunition. The weight of the can is in the 15 ounce range, utilizing a titanium outer tube and front cap and a 17-4PH core. The MPA556S-II can handle full auto fire on full length barrels in 5.56, so it is built to last.

The MPA22 Murmur II utilizes a 17-4PH monocore baffle with a 304L stainless steel outer tube, front and rear cap and is the quietest 22 MPA has produced to date. The DB ratings of this suppressor are in the 114-115 DB range (10 shot weighted average using NI Labview Software / GRAS ¼” MICs) and due to the single monocore design, makes servicing and cleaning the suppressor quite easy. It is laser engraved and includes a unique MPA texturing on the outer tube. The Murmur II is finished in cerakote, weighs 5.4 oz. and measures 5.8 in. length and 1 inch in diameter. . This suppressor is rated for applications in .22LR, 17HMR, 22 WMR and 5.7x28mm. Spanner wrench included.

MasterPiece Arms tested the MPA556S-II and Murmur II sound suppressors on MPA’s state-of-the-art Decibel Metering System. Only a few large suppressor manufacturing companies use this metering system and MasterPiece Arms is proud to be one of them. The software used to test the sound suppressors includes National Instruments NI USB-4432 DAQ, National Instruments Labview Full Development System and National Instruments Sound and Vibration Toolkit. The microphone included in the test was a GRAS ¼” Microphone Type 40BD with Preamplifier 26CB with TEDS info. Finally, the calibrator used was a GRAS Model 42AB 1khz, 114 DB. MasterPiece Arms’ sound suppressors all offer the user the low decibel reading on the MPA test equipment under the most ideal testing parameters providing for a comfortable sound experience.